The GitHub Copilot SDK exposes the same agent runtime behind Copilot CLI, allowing developers to invoke an AI agent programmatically without building their own orchestration. It provides cross-language libraries (Python, TypeScript, Go, .NET, Java, Rust) that handle agent planning, tool invocation, and file edits. Developers define agent behavior while the SDK manages the execution runtime, making it a production-tested foundation for embedding agentic capabilities into applications and services.